With a skip and a jump, two-year-old shelter dog Coco followed the trail of treats lined on a new agility plank at the Southold Town Animal Shelter with laser focus Thursday afternoon.

Coco, a petite Boston Terrier mix, was brought back to the shelter for a second time about a month ago. Her previous owners cited behavioral issues, especially around men, as the reason for Coco’s return.

But you’d never know it by watching her Thursday.

Within minutes of installing the course, which includes a see-saw, pause table and a-frame stations you’re likely to see on televised dog competition shows, Coco was running around and learning new tricks — even while being in the presence of men.

Already receiving help from trainer Gina Lepine of the North Fork Animal Welfare League — the nonprofit that runs the shelter — Coco is expected to flourish exponentially with teaching on the agility equipment.

“This equipment is great because she has been mentally worked out and physically worked out,” Ms. Lepine said, adding the course will help all the shelter’s other 14 adoptable dogs get a leg up. “Dogs need to think. Agility builds confidence and focus in a dog. It makes them better pets. And it makes them more adoptable.”

The agility course is not limited to young pups like Coco either.

With the exception of the shelter’s senior dogs, considered over 13 years old, all the adoptable dogs will have a chance to learn and play on the equipment.

Perhaps even more inspiring than Coco’s transformation is the story behind the equipment that is helping her and they other pups improve.

Maddalena Mineo, a Mattituck High School senior, spent her winter in her family’s basement designing and building the equipment for the agility course.

The 17-year-old lifelong animal lover, who formerly penned the ‘Critter Column’ highlighting adoptable pets for her high school newspaper the Tucker Times, used the guidance of a book to construct the course.

This project earned Ms. Mineo the Girl Scout’s highest honor the Gold Award, which she is expected to receive this summer.

“When it came time to pick a project, I came to the animal shelter,” she said. “Animals have always been a big part of my life.”

Ms. Mineo’s inquiry to help the shelter last fall came at the perfect time, said Marlene Ferber, who is on the shelter’s board of directors.

The agility garden is something the nonprofit has been considering for a while as a means to improve the facility for the dogs and make it more inviting for the general public to visit.

The effort started last year with the completion of the shelter garden in the front of the building. But the concept of second phase — the agility garden— was truly kicked into motion when Ms. Mineo approached the shelter last fall to do the work, Ms. Ferber said.

“Maddalena is so handy,” Ms. Ferber said. “We are so excited to be working with her.”

Months in the making, the excitement could be felt by at the installation last week.

“It is great to see everyone’s reaction,” said Ms. Mineo, who is planning on attending Alfred University in the fall to become a veterinary technician. “I was horrible at workshop, so this makes me feel better about that.”

Ms. Mineo said her family and community donations helped the concept take shape. In particular, a $500 donation — used for the supplies to make the course— was made by The Mattituck Lions Club through Darla Doorhy. The memory of Ms. Doorhy’s 20-year-old daughter, MHS graduate Kaitlyn Doorhy, is expected to be honored at the course at a later time. Kaitlyn, a friend of Ms. Mineo’s, was tragically killed in a car accident less than a year ago.

In the future, the NFAWL hopes to line the agility garden with bushes to prevent distraction by other dogs in the outdoor pens.

They also plan to improve the shelter’s outside area further by adding benches for visitors to play with the dogs, Ms. Ferber said.